You could maybe do a canal from the Gulf of California to the Salton sink and desalinate the water, which would help somewhat with the demands on water from the

You could maybe do a canal from the Gulf of California to the Salton sink and desalinate the water, which would help somewhat with the demands on water from the Colorado River. There are diplomatic (the canal would have to pass through Mexico to reach the US) and environmental concerns (where do you put the brine after you desalinate the water? Either you dump it in the Salton Sea, which is already an environmental catastrophe, or you pipe it _back_ across Mexico and dump it back into the Gulf of California, where you also cause a lot of damage if you don't distribute it well enough). Still, it's a question worth asking and I don't know why you're being downvoted.